Help, Trans Leak turbo 350

I have a truck i just swapped the engine and trans in. I put a turbo 350 trans in it and it is leaking pretty good. It appears to be coming from above the pan out of an electrical unit. Nothing is plugged into it. Not sure what it is. It is on drivers side. Im unsure what i can do to stop leak. or if i can replace plug. havent looked close enough to see how it comes out but would appreciate any advice. Thanks.

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this is a pic of a turbo350. i believe same style or close. the red circle points out what is leaking.

I had a leak in a turbo 350, it was from the port where the speedo cable connected. It's been awhile, but I think it was in that location. It required a new seal. Afraid I can not tell you how it was replaced, I had a shop do it.